Buffalo WLI-TX4-AG300N Handbuch Seite 13

Click Select Wireless Mode from the Information page to
change which is used when both wireless-a and wireless-g
networks are available.
Click the dropdown arrow to change the
a/g mode setting. 802.11a Preferred will
connect to wireless-a networks if available,
but will still connect to a wireless-g network if that's all that's
available. 802.11g Preferred will connect to wireless-g networks
if available, but will still connect to a wireless-a network if that's
all that's available. 802.11a Only will only connect to wireless-a
networks, even if wireless-g networks are available. 802.11g Only
will only connect to wireless-g networks, even if wireless-a networks
are available.
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